A dispute between the U.S. Congress and the Bush administration over a plan to sell F-16 fighter aircraft to Pakistan spilled into the open Thursday during a congressional hearing on Capitol Hill. Some lawmakers say they were not properly consulted on key aspects of the plan, and raised concerns ranging from technology proliferation to political stability and human rights in Pakistan.

President Bush authorized the sale of F-16 aircraft to Pakistan in 2005, reversing a policy in effect for at least 15 years against such transfers because of nuclear concerns.

India has reiterated its opposition, describing the sale as not conducive to improving ties between India and Pakistan.

Lawmakers are furious with what they see as inadequate State Department consultation with Congress.

House International Relations Committee Chairman Henry Hyde accuses the State Department of ignoring Congress' role and violating understandings on congressional notification regarding arms sales. "It represents a deliberate and we believe, wholly inappropriate maneuver by the State Department to diminish the Congress' lawful oversight of arms sales," he said.

Pakistan would receive 18 F-16 jets under the five-billion dollar deal, with an option to purchase 18 more.

But primary among lawmaker's concerns is their belief that the Pakistani government cannot ensure technology will not fall into the hands of China or others.

Senior committee Democrat Tom Lantos agrees with administration justifications that the sale will help Pakistan meet legitimate security needs, but underlines his concern. "Pakistani export controls are so lax as to have allowed A.Q. Khan to provide the crown jewels of Pakistan's nuclear weapons development program to states such as North Korea and Iran. The administration's plan is inadequate to safeguard U.S. technology properly and to protect U.S. national security against espionage and compromise in Pakistan," he said.

The hearing was scheduled for last week but postponed amid often tense behind-the-scenes negotiations with the State Department. A similar Senate hearing was also postponed.

Lawmakers accused the State Department of arrogance in how it handled notification, with Lantos alleging what he called a calculated attempt to prevent Congress from trying to alter the current security plan for the planes.

John Hillen, assistant secretary of state for political-military affairs denies that, and defends the security plan. "The administration very carefully considered the potential risks of diversion of U.S. technology and equipment and we are taking appropriate steps to minimize those risks. Furthermore, the government of Pakistan, including the Pakistan Air Force has been extremely cooperative in responding to our concerns on the security of aircraft and technology," he said.

The State Department position that it did nothing wrong in consulting with Congress sparked this angry exchange between Hillen and Democratic Congressman Brad Sherman:

HILLEN: "I have taken this process quite seriously as a custodian of the public trust."

SHERMAN: "Your job is to disenfranchise our constituents and to make sure that nothing that comes from Congress affects this deal in any way and you've done it spectacularly well."

Republican Dan Burton shares the worries about security, but says Pakistan's role in the war on terrorism justifies the sale of F-16s. "We should show some support for Pakistan with this sale," he said.

Another Republican, Congressman Dana Rohrabacher, disagrees. "The F-16 is an offensive weapons system. It can drop nuclear weapons. And it is designed to make war on countries that have sophisticated air forces, not the Taleban, not radical Islam," he said.

Assistant Secretary Hillen said the F-16s for Pakistan will not be capable of carrying nuclear weapons, although he acknowledged they could be modified.

In a statement accompanying notification to Congress, the Pentagon said the Pakistani purchase would "not significantly reduce India's quantitative or qualitative military advantage" and that it would neither affect the regional balance of power nor introduce a new technology in the region.